#include <iostream>
#include <string.h>
using namespace std;

// 消除字符串中重复项，并按照原来的顺序输出
int main()
{
    char p[100];
    while(cin >> p) {
        char table[125] = {0};
        int n = strlen(p);
        for (int i = 0; i < n; i++) {
            if (table[p[i]] == 0) {
                table[p[i]] = 1;
                cout << p[i];
            }
        }
        cout << endl;
    }
    return 0;
}